Pt. 36, App. G

14 CFR Ch. I (1-1-19 Edition)

pounds (1.650 kg.) the limit increases at the
rate of 1 dB/165 pounds (1 dB/75 kg.) to 82
dB(A) at 3,630 pounds, after which it is constant at 82 dB(A). However, airplanes produced under type certificates covered by this
paragraph must also meet paragraph (d) of
this section for the original issuance of
standard airworthiness certificates or restricted category airworthiness certificates
if those airplanes have not had flight time
before the date specified in that paragraph.
(c) For airplanes for which application for
a type certificate is made on or after January 1, 1975, the noise levels may not exceed
the noise limit curve prescribed in paragraph
(b) of this section, except that 80 dB(A) may
not be exceeded.
(d) For airplanes for which application is
made for a standard airworthiness certificate
or for a restricted category airworthiness
certificate, and that have not had any flight
time before January 1, 1980, the requirements of paragraph (c) of this section apply,
regardless of date of application, to the
original issuance of the certificate for that
airplane.
[Doc. No. 13243, 40 FR 1035, Jan. 6, 1975; 40 FR
6347, Feb. 11, 1975, as amended by Amdt. 36-
6, 41 FR 56064, Dec. 23, 1976; Amdt. 36-6, 42 FR
4113, Jan. 24, 1977; Amdt. 36-9, 43 FR 8754,
Mar. 2, 1978; Amdt. 36-13, 52 FR 1836, Jan. 15,
1987; Amdt. 36-16, 53 FR 47400, Nov. 22, 1988;
FAA Doc. No. FAA-2015-3782, Amdt. No. 36-
31, 82 FR 46131, Oct. 4, 2017]

APPENDIX
NOISE

G TO PART 36 - TAKEOFF
REQUIREMENTS FOR PROPELLER-DRIVEN
SMALL AIRPLANE
AND PROPELLER-DRIVEN, COMMUTER
CATEGORY AIRPLANE CERTIFICATION
TESTS ON OR AFTER DECEMBER 22,
1988
PART A - GENERAL

Sec.
G36.1 Scope.
PART B - NOISE MEASUREMENT

G36.101 General Test Conditions.
G36.103 Acoustical measurement system.
G36.105 Sensing, recording, and reproducing
equipment.
G36.107 Noise measurement procedures.
G36.109 Data recording, reporting, and approval.
G36.111 Flight procedures.

spaschal on DSK3GDR082PROD with CFR

PART C - DATA CORRECTIONS

G36.201 Corrections to Test Results.
G36.203 Validity of results.
PART D - NOISE LIMITS

G36.301 Aircraft Noise Limits.

PART A - GENERAL

Section G36.1 Scope. This appendix prescribes limiting noise levels and procedures
for measuring noise and adjusting these data
to standard conditions, for propeller driven
small airplanes and propeller-driven, commuter category airplanes specified in SectionSection 36.1
and 36.501(c).
PART B - NOISE MEASUREMENT

Sec. G36.101 General Test Conditions.
(a) The test area must be relatively flat
terrain having no excessive sound absorption
characteristics such as those caused by
thick, matted, or tall grass, by shrubs, or by
wooded areas. No obstructions which significantly influence the sound field from the airplane may exist within a conical space above
the measurement position, the cone being
defined by an axis normal to the ground and
by a half-angle 75 degrees from the normal
ground axis.
(b) The tests must be carried out under the
following conditions:
(1) No precipitation;
(2) Ambient air temperature between 36
and 95 degrees F (2.2 and 35 degrees C);
(3) Relative humidity between 20 percent
and 95 percent, inclusively;
(4) Wind speed may not exceed 10 knots (19
km/h) and cross wind may not exceed 5 knots
(9 km/h), using a 30-second average;
(5) No temperature inversion or anomalous
wind condition that would significantly alter
the noise level of the airplane when the nose
is recorded at the required measuring point,
and
(6) The meteorological measurements must
be made between 4 ft. (1.2 m) and 33 ft. (10 m)
above ground level. If the measurement site
is within 1 n.m. of an airport meteorological
station, measurements from that station
may be used.
(c) The flight test procedures, measuring
equipment, and noise measurement procedures must be approved by the FAA.
(d) Sound pressure level data for noise
evaluation purposes must be obtained with
acoustical equipment that complies with
section G36.103 of this appendix.
Sec. G36.103 Acoustical Measurement System.
The acoustical measurement system must
consist of approved equipment with the following characteristics: (a) A microphone system with frequency response compatible
with measurement and analysis system accuracy as prescribed in section G36.105 of this
appendix.
(b) Tripods or similar microphone mountings that minimize interference with the
sound being measured.
(c) Recording and reproducing equipment
characteristics, frequency response, and dynamic range compatible with the response

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